Fastening machines

ABSTRACT

A fastening machine (1) has guide block (11) with a rivet delivery passage (12). Rivets (17) are supplied from a source via tube (22) and are delivered to the rivet delivery passage (12) by a rivet supply passage (20). The head of the rivet (17) is engaged by spring-loaded balls (60) to hold the rivet (17) in alignment with the rivet delivery passage (12) and a punch (16). When a limit switch (30) detects the presence of a rivet (17) in the rivet delivery passage (12), the punch (16) is advanced and the rivet (17) is releasably supported by the balls (60) and secondary balls (60A) as it is advanced to work pieces to be secured together.

BACKGROUND OF THE INVENTION

1. Field of the Invention

THIS INVENTION relates to improved fastening machines. In particular,this invention relates to improved punch/setting tool combinations forfastening machines.

2. Prior Art

U.S. Pat. No. 4,615,475 (Fuhrmeister) (=AU-B-28506/84(566811)=International Publication No. WO 84/04710) discloses a feederfor headed fasteners, where the fasteners, mounted in tape, aresequentially advanced into alignment with the punch and die assembly ofa fastening machine by an oscillating actuator, which is timed by theplunger holding the punch, the actuator releasably engaging the stems ofthe fasteners to advance the fasteners.

The feeder, and the fastening machine, has proved commerciallysuccessful in a wide range of industries. There are certainapplications, however, eg. in the automotive and white goods industries,where the dimensions of the feeding head preclude the use of the abovedescribed type of fastening machine to fasten components together, wherelimited space is available.

In addition, the minimum radius of curvature of the tape entering andleaving the feeder head also limits the reduction of size of the feederhereinbefore described to suit such applications.

In our International Application No. PCT/AU94/00013 (InternationalPublication No. WO 94/15730), we disclose improved setting tools for thedelivery of fasteners to a workpiece, where the fasteners are centeredand stabilized by, eg. pins, balls, fingers, or resilient annular discsin the fastener delivery passage. The setting tools are particularlysuitable for fasteners where the stem (or shank) length is less than, orequal to, the diameter of the head.

In certain applications, limited access to the workpieces being fastenedprecludes the use of the setting tools disclosed in the aboveInternational Application.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improvedfastening machine which has better nose access.

It is a preferred object to provide a fastening machine where thecentralizing elements of the fastening machine can be raised to aposition unrelated to fastener length.

It is a further preferred object to provide a vacuum to the fasteneractuator to releasably retain the fastener thereto as the fastener isdelivered to the workpiece.

It is a still further preferred object to provide a machine where thefastener is centralized on the fastener actuator as it is advanced inthe fastener delivery passage.

It is a still further preferred object to provide a machine where thefasteners are fed to the setting tool by tape, blow feed, manually orthe like.

The term "fastener" shall include rivets, screws and other likefastening devices.

The term "fastener actuator" includes a punch when the fastener is arivet; a driver when the fastener is a screw; or other toolingappropriate to insert or apply the fastener after its delivery by thenose assembly.

The term "stem" of a fastener shall be hereinafter used to also includea "shank" of a fastener.

The term "fastener support means" includes means which guide or orientan advancing fastener as occurs, eg. in tape feed machines, whereinitial support may be by the tape, and the term includes means whichengage either or both of the head and stem of an advancing fastener.

In one aspect, the present invention resides in a fastener actuator fora fastening machine wherein:

releasable fastener retaining means on a fastener engaging nose of theactuator releasably secures a fastener to the nose as the fastener isadvanced towards a workpiece.

In a second aspect, the present invention resides in a setter tool andfastener actuator assembly for a fastening machine including:

a setter tool having a nose piece with a fastener delivery passagetherein and a fastener supply passage to enable fasteners to betransferred from a fastener supply to the fastener delivery passage;

a fastener actuator slidably mounted for movement through the fastenerdelivery passage to move a fastener therefrom to a workpiece to befastened thereby;

means operable to advance the fastener actuator through the fastenerdelivery passage, and

releasable fastener retaining provided on a fastener engaging nose onthe fastener actuator to releasably secure a fastener to the nose as theactuator moves through the fastener delivery passage and is advancedtowards the workpiece.

The releasable fastener retaining means may include a vacuum; a magnet(permanent or switched electromagnet); contact adhesive or othersuitable means.

In third and fourth aspects, the present invention resides in afastening machine incorporating the fastener actuator of the firstembodiment, or the assembly of the second embodiment, respectively.

Where the releasable fastener retaining means is a vacuum, preferably atleast one passage is provided through the actuator, open at one end tothe fastener engaging nose, and connected at its other end to a sourceof vacuum via a control valve. The source of vacuum may be connected toa chamber which surrounds a portion of the actuator, and port means inthe actuator are selectively connected to the vacuum chamber as theactuator is advanced to provide the control valve means.

The fastener may be centralized relative to the fastener deliverypassage and the actuator by balls, pins, fingers, rings or the like inthe passage, or be received in a recess in the nose of the actuator, orhave a protrusion or protrusions on the fastener head to engage acomplementary recess or recesses on the nose.

BRIEF DESCRIPTION OF THE DRAWINGS

To enable the invention to be fully understood, preferred embodimentswill now be described with reference to the accompanying drawings, inwhich:

FIGS. 1 and 2 show the relative dimensions of a rivet and a passagetherefor;

FIG. 3 is a sectional side view of a conventional fastening machine (notforming part of the present invention);

FIG. 4 is a sectional side view of a first embodiment of the invention;

FIG. 5 is a sectional side view of a second embodiment;

FIG. 6 is a bottom sectional view taken on line 6--6 on FIG. 5;

FIG. 7 is a sectional side view of a third embodiment;

FIG. 8 is a bottom plan view of the third embodiment;

FIGS. 9 to 14 are sectional side views of respective fourth to ninthembodiments;

FIG. 15 is a sectional end view of the embodiment of FIG. 14;

FIGS. 16 to 19 are sectional side views of tenth to thirteenthembodiments of the invention;

FIGS. 20 and 21 are sectional side views of a fourteenth embodiment;

FIGS. 22 to 24 are sectional side views of fifteenth to seventeenthembodiments of the invention;

FIG. 25 is a sectional side view showing the use of the vacuum to enablethe handling of rivets in a transfer station; and

FIG. 26 is a sectional plan view taken on line 26--26 on FIG. 25.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIGS. 1 and 2, a rivet 10 (FIG. 1) with a diagonal dimensionD (eg. 8.1 mm) will not tumble when passed through a tube or body 20with a bore or passage 22 of small dimension d (ie. 8.00 mm) (FIG. 2).The problem of rivets 10 tumbling (and jamming) in a passage 22 is morelikely to occur when the head diameter 0 D is greater than the stemlength L (FIG. 1).

FIG. 3 shows a conventional (ie. prior art) fastening machine 30 wherethe distance A between the centralizing balls 31 in the delivery passage32 are spaced a distance A from the end 33 of the fastening machine,dependent on the length L of the rivet 10. The punch 34 has a plainrivet engaging nose 35. The centralizing balls 31 must be no greaterthan a distance A from the end 33 to align the rivets 10 with the punch34.

Referring now to the first embodiment of FIG. 4, the riveting machine100 has a setting tool 110 with a fastener delivery passage 111therethrough, which receives rivets from a source (eg. tape) (not shown)via a delivery passage 101 transverse to the fastener delivery passage111. A single layer of centralizing balls 112, backed by resilientsprings 113, are provided adjacent the upper end of the fastenerdelivery passage 111 to centralize the rivets relative to the passage111 and the nose 121 of the punch 120 mounted on the piston 130 in thecylinder housing or guide bush 140 of the riveting machine 100.

A vacuum passage 122 extends coaxially within the punch 120 and isconnected to a vacuum passage 132 in the piston 130. The passage 132 isconnected to a passage 152 through a vacuum fitting 150, fitted to thecylinder 140, and slidably sealed to a bore 133 in the upper end of thepiston 130.

A vacuum line 153 connects the vacuum fitting 150, via elbow 154, to thevacuum port 155 of a venturi 156.

Compressed air from the air compressor 157 is directed by theelectrically controlled vacuum valve 158 to the venturi 156 (andsilencer 159) to generate a vacuum in the venturi 156. When the vacuumvalve 158 is switched off, the double solenoid ejector valve 160 isopened to apply a positive pressure to vacuum port 155 to break thevacuum down more rapidly.

A rivet is supplied to the fastener delivery passage 111 (via the supplypassage 101) and the punch 120 is advanced towards the workpiece notshown, supported on an upsetting die (not shown) aligned with the punch120. (The cylinder 140 and upsetting die may be mounted on respectivearms of a C-frame 190.)

As, or just before, the nose 121 of the punch 120 contacts the rivethead, the vacuum source is connected (by opening valve 158) to thevacuum passage 122 and so the rivet is drawn onto the punch nose 121.The balls 112 centralize the rivet on the nose 121 and the punch 120advances the rivet through the fastener delivery passage 111 to theworkpiece. When the rivet has been upset by the die, the vacuum sourceis disconnected from the vacuum passage 122 (by closing valve 158) andthe punch 120 is retracted. (While the punch is being retracted, a briefblast of pressurised air may be blown through the vacuum passage (byopening valve 160) to clear any debris therefrom (and from the fastenerdelivery passage 111) and/or to selectively release the fastener fromthe punch). It will be noted that the rivet 10, held to the punch 120 bythe vacuum, will not tumble or tilt as it is advanced to the workpiece,and the centralizing balls 112 of the setting tool 110 can be spaced adistance much greater than the distance A of the conventional fasteningmachine (30 FIG. 3) from the workpiece.

In the fastening machine 200 of FIGS. 5 and 6, a vacuum chamber 223surrounds the punch 220 and is isolated from the cylinder or guide bush140, containing the piston 230, by seals or at lapped spool 241 and241A. Vacuum port 224 in the punch 220 selectively connects the vacuumpassage 222 in the piston to the vacuum chamber 223 when the punch 220has, or is just about to, engage the rivet head and so the punch 220 andchamber 223 co-operate to provide the timed control vacuum for thevacuum passage 222. The vacuum chamber 223 has an inlet 225 mounted onone side of the punch guide head 226, and is connected to the chamber bya port 227.

In this embodiment, the balls 212 are spaced a greater distance belowthe nose 221 of the punch 220 and so the balls 212 will centralize therivet on the punch 220 after the rivet has been secured to the nose 221.

The fastener supply passage 201 receives the rivets, via a curvedpassage 207 in the setting tool 210 from a tube 208 connected to aremote blow feeder (not shown). Three sets of balls 212A engage andsupport the rivet in the fastener delivery passage 211 before the punch220 is advanced. A micro switch 216 has a trigger 217 to detect thepresence of a rivet in the delivery passage 211, the micro switchpreventing advance of the punch 220 when no rivet is detected.

In the third embodiment of FIGS. 7 and 8, the fastening machine 300 hasits vacuum fitting 350 mounted transversely on the piston 320 and isconnected to the vacuum passage 322 by the vacuum port 324. An elongateslot 348 is provided in the cylinder or guide bush 340 to allow thevacuum fitting to advance and retract with the punch 320. The vacuumconnection to the vacuum passage 322 is controlled as hereinbeforedescribed with reference to FIG. 4.

The fastening machine 400 of the fourth embodiment (see FIG. 9) allows asimple nose design for the setting tool 410 and is particularly suitablefor rivets 10 where the head diameter OD is greater than the stem lengthL. Each rivet is supplied via a tape and pushed through the supplypassage 401 to the fastener delivery passage 411 and immediatelycentralized by the balls 412 as the punch 420 is advanced to engage therivet. The vacuum applied to the rivet head via vacuum passage 422retains the rivet on the punch nose 421.

FIG. 10 shows a fastening machine 500 where the nose 514 of the settingtool 510 is spaced a distance H from the workpieces 580, 581 (and die570) to prevent damage or marking of the upper surface of workpiece 580.The rivet 10 is carried and retained (via vacuum connected to vacuumpassage 522) on the nose 521 of the punch 520 over the distance H, afterhaving been centralized by the balls 512.

The fastening machine 600 (see FIG. 11) is similar to the fasteningmachine 500 of FIG. 10, and shows how the machine can be used whereaccess to the workpieces 680, 681 and die 670 is difficult and/ordelicate. Once again, the rivet 10 is releasably secured to the nose 621of the punch 620 via the vacuum in the vacuum passage 622.

The fastening machine 700 (FIG. 12) shows the fixing of a deep channelworkpieces 780 to a second workpiece 781 where access for the nose 714of the setting tool 710 is impossible. The nose 714 may have a resilientblock or pad 715 to preclamp and/or protect the workpiece 780, 781before the rivet 10, secured on the nose 721 of the punch 720 via vacuumconnected to vacuum passage 722, is advanced by the punch 720 and upsetby the die 770.

The fastening machine 800 of FIG. 13 enables preclamping of the deepchannel workpiece 880 to the workpiece 881 by the nose 814 of theupsetting tool 810 where access is limited. A small cross-sectional areaof the nose 814 or, alternatively, high loads can be applied to the nose814 (without affecting the stress levels which would normally be limitedby the provision of the centralizing balls 812 near to the bottom of thesetting tool 810). Both pre-clamping and post-clamping of the workpieces880, 881 can be affected, while the rivet is secured to the punch 820 byvacuum applied to vacuum passage 822 as herein before described.

FIGS. 14 and 15 show a fastening machine 900, similar to the fasteningmachines 600 and 700 of FIGS. 11 and 12, where the punch 920 advancesthe rivet 10 into a channel section workpiece 980, to be fixed to asecond workpiece 981. As the workpieces 980, 981 are curved in sideview, the distance that the punch 920 must advance the rivet isincreased.

FIG. 16 shows how a machine 1000, similar to the fastening machines 600,700 of FIGS. 11 and 12 can fix a box section workpiece 1080 to aworkpiece 1081 where the punch 1020 advances the rivet through an accesshole 1082.

The fastening machine 1100 of FIG. 17 is generally similar to themachine 800 of FIG. 13, except that the nose 1114 is relieved at itsforward end.

In all of the embodiments of FIGS. 4 to 17, the rivets have beencentralised relative to the punches by balls or the like in the fastenerdelivery passages.

In FIG. 18, a conical protrusion 11 on the rivet 10 engages a conicalsocket 1227 in the vacuum passage 1222 at the nose 1221 of the punch1220 (of fastening machine 1200) to centralize the rivet 10 to the punch1220, while in FIG. 14, the head 12 of a rivet 10 is received in acomplementary socket or recess 1327 in the nose 1321 of the punch 1320,the socket 1327 being connected to the vacuum passage 1322 of fasteningmachine 1300.

The machine 1400 (see FIGS. 20 and 21) has a recess 1427 in the nose1421 of punch 1420, the recess 1427 being dimensioned to receive thehead 12 of the rivet 10.

As shown in FIG. 21, the nose 1421 of the punch 1420, in theconfiguration of a peripheral flange, forms an annular recess in theupper workpiece 1483, ie. it "coins" the parent workpiece material aboutthe rivet head 12, after the rivet 10 has been set, to improve thefatigue strength of the joint and/or the aesthetic appearance thereof.

The "coining" of the workpieces is particularly important in themanufacture to include panels from aluminium sheets.

The machine 1100 of FIG. 17 can achieve the same objective, except thatthe "coining" is independent of the punch and can be effected, pre- orpost-insertion of the rivet in the workpieces.

The recesses 1227, 1327, 1427 in the punches 1220, 1320, 1420, tocentralise the rivets 10, may be employed in applications where thespace adjacent the workpiece is so tight that centralizing elements,such as the balls, cannot be provided in the setter tools. They may alsobe used where a large diameter punch must be used to "coin" the materialof the workpiece(s) around the joint, and centralizing elements for therivet would be ineffective (ie. too far away from the rivets or openedby the punch, not the rivets).

As an alternative to vacuum to releasably secure the rivets to the punchnose, contact adhesive may be applied to the heads. 12 of the rivets 10,before the rivets are engaged by the punch. In FIG. 22, a roller 1502 isprovided in the delivery passage 1501 of the setting tool 1510 onfastening machine 1500. A port 1503 connects the roller 1502 to areservoir 1504 of contact adhesive. As the rivets pass through thedelivery passage 1501 to the fastener delivery passage 1511, a thinlayer of contact adhesive is applied to the rivet heads 12 by the roller1502 to enable the rivets to releasably adhere to the nose of the punch(not shown) as the latter advances the rivets to the workpiece(s).

In FIG. 23, the punch 1620 of fastening machine 1600 has anelectromagnet 1626 in a passage 1622 in the punch 1620. Theelectromagnet 1626 is connected to a battery (DCV) via a suitable switch(not shown) to selectively retain the rivet on the nose (1621 of thepunch 1620.

In FIG. 24, a permanent magnet 1725 is provided in the passage 1722 inthe punch 1720 of fastening machine 1700. (Preferably, a thin shield isprovided in the punch 1720 to protect the punch from becomingmagnetised.) The magnet 1726 provides an attractive force to releasablyretain the rivet 10 on the punch nose 1721.

Referring now to FIGS. 25 and 26, a fastening machine 1800, generallysimilar to the fastening machine 200 of FIG. 5, is supplied with rivetsby a transfer station 2000.

Rivets 10, in a tape 19, are released from the tape by a releaseactuator 2020, which advances the rivets 10 to a stop 2001, in alignmentwith a transfer actuator 2040. When a rivet 10 is received at the stop2001, timer means (not shown) cause the pneumatic cylinder 2041 toadvance the transfer actuator 2040 to deliver the rivet through thesupply passage 1801, to be engaged by the balls 1812 to centralize therivet in the delivery passage 1811 in the setter tool 1810. Vacuumpassages 2022 and 2042 in the actuators 2020 and 2040 are selectivelyconnected to the vacuum source to which passage 1822 in punch 1820 isselectively connected to enable the rivets 10 to be releasably securedto the actuator 2020 and 2040 as the rivets are transferred from thetape 19 to the stop 2001, and from the stop 2001 to the supply passage1801 in the fastening machine 1800.

In a modified embodiment, the rivets 10 may be supplied to the stop 2001by a blow-feeding tube (equivalent to tube 208 in FIGS. 5 and 6), andthe rivets 10 are then delivered to the supply passage 1801 by thetransfer actuator 2040.

Various changes and modifications may be made to the embodimentsdescribed and illustrated without departing from the scope of thepresent invention defined in the appended claims.

We claim:
 1. A fastener actuator for a fastening machine, wherein theactuator advances a fastener toward a workpiece for securing thefastener to the workpiece, comprising:means defining a fastener deliverypassage downwardly through which the fastener passes, a fastener supplypassage for sequentially delivering fasteners to the fastener deliverypassage, and wherein the fastener actuator is vertically movable throughthe fastener delivery passage, the actuator including a nose at itsleading end for engaging a fastener and advancing the same toward theworkpiece, the actuator being provided with an internal passage one endof which is open to the nose of the actuator and another end of which isconnected to a vacuum source through a control, whereby connecting theinternal passage to the vacuum source effects vacuum retention of thefastener on the nose of the actuator to maintain orientation of thefastener as the actuator advances toward the workpiece.
 2. The fasteneractuator of claim 1, wherein the means defining a fastener deliverypassage comprises a setting tool, the setting tool also being formedwith the fastener supply passage, and further including a plurality ofresiliently biased centralizing balls provided adjacent the upper end ofthe delivery passage to centralize the fastener with respect to avertical axis of the delivery passage.
 3. The fastener actuator of claim1, wherein the source of vacuum is connected to a vacuum chamber whichsurrounds a portion of the actuator, the actuator being formed with aport which communicates with the internal axial passage of the actuatorand is selectively connected to the vacuum chamber as the actuator isadvanced depending on the position of the actuator, the advancement ofthe actuator establishing vacuum connection to the internal passagewhereby the nose of the actuator releasably retains the fastener untilthe vacuum is released.
 4. The fastener actuator as claimed in claim 1,wherein two workpieces are secured by each fastener, and wherein thenose piece engages one of the workpieces to preclamp the workpiece to anupsetting die before the fastener fastens the workpieces together. 5.The fastener actuator as claimed in claim 1, wherein the leading end ofthe actuator nose forms a peripheral flange around a head on thefastener to deform the workpieces about the fastener.
 6. The fasteneractuator as claimed in claim 1, wherein the fasteners are supplied tothe fastener supply passage by a fastener supply tape.
 7. The fasteneractuator of claim 6, wherein the fasteners are fed to the supply passagethrough a transfer station, the transfer station having a transferactuator aligned with the fastener supply passage, and a fastener stop,and releasable fastener retaining means are provided on the transferactuator to releasably secure the fastener to the transfer actuator asthe fastener is transferred from the fastener stop to the fastenersupply passage.
 8. The fastener actuator as claimed in claim 7, whereinthe fastener supply tape is spaced from the fastener stop, and furtherincluding a fastener release actuator which transfers the fastenersseriatim from the tape to the fastener stop, the fastener releaseactuator being provided with vacuum means for releasably retaining afastener while being transferred.
 9. The fastener actuator as claimed inclaim 1, wherein the fasteners are fed to the fastener supply passage bya blow feeder.
 10. An fastener actuator for advancing a fastener towarda workpiece for securing the fastener to the workpiece, comprising:ahousing, a setting tool operatively connected to the housing, thesetting tool being formed with a fastener supply passage for receivingfasteners seriatim from a fastener source, and a fastener deliverypassage through which a fastener is directed to a workpiece, saidsetting tool further including a plurality of resiliently biasedcentralizing balls provided adjacent the upper end of the deliverypassage to centralize the fastener with respect to a vertical axis ofthe delivery passage, and wherein the fastener actuator is mounted forvertical reciprocal movement in the housing and through the fastenerdelivery passage, the actuator including a nose at its leading end forengaging a fastener and advancing the same toward the workpiece, theactuator being provided with an internal axial passage one end of whichis open to the nose of the actuator and another end of which isconnected to a vacuum source through a control, whereby connecting theinternal passage to the vacuum source effects vacuum retention of thefastener on the nose of the actuator to maintain orientation of thefastener as the actuator advances through the delivery passage towardthe workpiece.
 11. The fastening machine of claim 10, wherein the sourceof vacuum is connected to a vacuum chamber which surrounds a portion ofthe actuator, the actuator being formed with a port which communicateswith the internal axial passage of the actuator and is selectivelyconnected to the vacuum chamber as the actuator is advanced depending onthe position of the actuator, the advancement of the actuatorestablishing vacuum connection to the internal passage whereby the noseof the actuator releasably retains the fastener until the vacuum isreleased.
 12. The fastening machine as claimed in clam 10, wherein twoworkpieces are secured by each fastener, and wherein the nose pieceengages one of the workpieces to preclamp the workpieces to an upsettingdie before the fastener fastens the workpieces together.
 13. Thefastening machine as claimed in claim 10, wherein the leading end of theactuator nose forms a peripheral flange around a head on the fastener todeform the workpieces about the fastener.
 14. The fastening machine asclaimed in claim 10, wherein the fasteners are supplied to the fastenersupply passage by a fastener supply tape.
 15. The fastening machine ofclaim 14, wherein the fasteners are fed to the supply passage through atransfer station, the transfer station having a transfer actuatoraligned with the fastener supply passage, and a fastener stop, andreleasable fastener retaining means are provided on the transferactuator to releasably secure the fastener to the transfer actuator asthe fastener is transferred from the fastener stop to the fastenersupply passage.
 16. An assembly as claimed in claim 15, wherein thefastener supply tape is spaced from the fastener stop, and furtherincluding a fastener release actuator which transfers the fasteners fromthe tape to the fastener stop, the fastener release actuator beingprovided with vacuum means for releasably retaining a fastener whilebeing transferred having releasably fastener retaining means.
 17. Thefastening machine as claimed in claim 10, wherein the fasteners are fedto the fastener supply passage by a blow feeder.